package com.liyou.full.filter;

import com.alibaba.fastjson.JSON;
import com.liyou.full.common.BaseContext;
import com.liyou.full.common.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    //支持通配符的路径匹配器
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.定义可以放行的路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        //2.获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求{}",requestURI);


        //3.检查路径是否匹配
        boolean check = check(urls,requestURI);

        //4.路径匹配，可以放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //5.检查是否已登录，已登录，可以放行
        if (request.getSession().getAttribute("employee") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }

        //6.判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user") != null){
            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        //7.未登录返回未登录结果
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(Result.error("NOTLOGIN")));
        return;

    }

    /**
     * 检查路径是否匹配的方法
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){

        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }

}
